1. Field of the Invention
The present invention relates to a liquid purifying attachment which is installed on or attached to a container that accommodates a certain liquid therein, and which is capable of delivering or dispensing the liquid while removing undesired particulate matters, such as soil particles, dust, microorganisms, bacteria, and virus. In particular, the invention is concerned with such a liquid purifying attachment which is simple and compact in construction, and which may be handled or manipulated with ease.
2. Discussion of the Prior Art
There has been a strong desire for a simple liquid purifying device which is used for purifying water from a river, for example, by removing undesired matters such as soil particles, so as to provide sterile water or drinking water for use in an emergency, which is available in the open air. Also is desired such a liquid purifying device for delivering a sterile pharmaceutical liquid which is free from bacteria, for example.
In view of the above, the assignee of the present application proposed liquid purifying devices as disclosed in laid-open Publication Nos. 62-125804 and 62-90706 of unexamined Japanese Patent Application and unexamined Japanese Utility Model Application, respectively. These devices use a container for accommodating a liquid, and a micro-porous membrane disposed in a liquid delivery path. The container is formed of a suitable elastic material so that the container body is elastically contracted by squeezing hand pressure, to deliver the liquid, and is elastically restored to its original shape upon releasing of the hand pressure. The micro-porous membrane permits the liquid to flow therethrough but inhibits passage of undesired particles or bacteria therethrough. In these devices, the bacteria, for example, contained in the liquid are removed or filtered out by the micro-porous membrane provided in the liquid delivery path, when the liquid is delivered or dispensed from the container.
However, the thus constructed liquid purifying device is not able to employ an elastically non-deformable or non-yieldable or relatively rigid container, such as a canteen formed of hard plastics, aluminum alloys, or other hard material, or a pressure-intolerant glass bottle containing a pharmaceutical liquid. Thus, the proposed device has some room for improvements.
In particular, when the liquid purifying device is carried over in the outdoors for providing sterile water or emergency drinking water, for example, the device is required to be compact and handy to carry, while assuring excellent durability.